Ignition Coil Secondary Signal Check

WARNING: This page is about a different car, the 1995 BMW 740iL, 1995 BMW 740i, and 1995 BMW 540i. However, it is still accessible from the selected car via links, so may be relevant.

Connect engine analyzer and Adapter (12-7-020) as described in IGNITION COIL PRIMARY SIGNAL CHECK. Remove ignition coil. Connect a spark plug wire (between coil and spark plug) to cylinder being tested. Connect inductive pick-up Blue lead, on lead to cylinder being tested. See Fig 2 .
Produce stopped signal on oscilloscope by pressing "R" button on tester. Display of ignition signal on oscilloscope will be strongest when inductive clip and Black lead are connected to same cylinder. Display on oscilloscope may be disturbed by neighboring ignition leads (this is normal).

IGNITION COIL RESISTANCE - Ohms 68°F (20°C)

Application

Primary

Secondary

530iT, 540i & 740i, 740iL

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⁽¹⁾	Information is not available from manufacturer.

Fig 1: Checking DIS Ignition Coil Primary Signal (540i, 740i, 740iL)

Fig 2: Checking DIS Ignition Coil Secondary Signal (540i, 740i, 740iL)